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Survey Data (survey + data)
Kinds of Survey Data Terms modified by Survey Data Selected AbstractsDETERMINATION OF MANATEE POPULATION TRENDS ALONG THE ATLANTIC COAST OF FLORIDA USING A BAYESIAN APPROACH WITH TEMPERATURE-ADJUSTED AERIAL SURVEY DATAMARINE MAMMAL SCIENCE, Issue 3 2004Bruce A. Craig Abstract In many animal population survey studies, the construction of a stochastic model provides an effective way to capture underlying biological characteristics that contribute to the overall variation in the data. In this paper we develop a stochastic model to assess the population trend and abundance of the Florida manatee, Trichechus manatus latirostris, along the Atlantic coast of the state, using aerial survey data collected at winter aggregation sites between 1982 and 2001. This model accounts for the method by which the manatees were counted, their movements between surveys, and the behavior of the total population over time. The data suggest an overall increase in the population from 1982 to 1989 of around 5%,7%, a reduction in growth or a leveling off (0%,4% annual growth) from 1990 to 1993, and then an increase again of around 3%,6% since 1994. In winter 2001,2002 (the most recent survey season for which analyses were done), we estimated the adult manatee population along the east coast of Florida to be 1,607 individuals (range = 1,353,1,972; 95% credible interval). Our estimate of manatee abundance corresponds well with maximum counts (approximately 1,600 manatees) produced during synoptic aerial surveys under optimal conditions. Our calculations of trends correspond well with mark and recapture analyses of trends in survival of adult manatees along the east coast through the early 1990s. Our population trend estimates since that time are more optimistic than those generated by mark-recapture models. [source] PRICE-SETTING BEHAVIOR IN TURKISH INDUSTRIES: EVIDENCE FROM SURVEY DATATHE DEVELOPING ECONOMIES, Issue 4 2008E30; D40 This study investigates the price-setting behavior of Turkish industries based on the results of a survey that was conducted by the Central Bank of the Republic of Turkey. The results show that, under normal conditions, the majority of the firms follow a time-dependent pricing rule but when significant events occur a substantial fraction of them alter their behavior to state-dependent reviewing. The median Turkish firm reviews its prices every month, but changes its prices four times a year. Price reviews and changes are affected by: the market share, price discrimination, customer type, firm size, and the existence of regulated prices. [source] FORECASTING MANUFACTURING OUTPUT GROWTH USING FIRM-LEVEL SURVEY DATATHE MANCHESTER SCHOOL, Issue 4 2005JAMES MITCHELL Traditionally forecasts of macroeconomic aggregates are extracted from prospective qualitative survey data by relating official data on the aggregate to both the proportion of survey respondents who are ,optimists' and the proportion who are ,pessimists'. But there is no reason to focus on these proportions to the exclusion of other possible means of aggregating and quantifying the underlying panel of respondent or firm-level survey responses. Accordingly in this paper we show how the panel of firm-level responses underlying these proportions can be exploited to derive forecasts of (aggregate) manufacturing output growth that do not lose information that may be contained in the pattern of individual responses. An application using firm-level prospective survey data from the Confederation of British Industry shows that the forecasts of manufacturing output growth derived using these ,disaggregate' methods mark an improvement over the so-called ,aggregate' methods based on use of the proportions data alone. [source] Zimbabwe's Child Supplementary Feeding Programme: A Re,assessment Using Household Survey DataDISASTERS, Issue 3 2002Lauchlan T. Munro In 1992,3 and 1995,6, Zimbabwe used a Child Supplementary Feeding Programme (CSFP) to combat child malnutrition during drought,induced emergencies. Previous evaluations of the CSFP relied on routine administrative data and key informant interviews and made only cursory use of available household survey data. These evaluations concluded that the CSFP was effective in preventing an increase in malnutrition among children under five, especially in 1992,3. The more,detailed analysis of household surveys provided in this article suggests that CSFP coverage was generally patchy and disappointingly low, especially in 1995,6. There is little evidence that children from poor or nutritionally vulnerable households got preferential access to supplementary feeding. The CSFP failed to feed many malnourished and nutritionally vulnerable children even in areas where the programme was operating. Household survey evidence suggests that the CSFP's impact on nutritional status was likely marginal, especially in 1995,6. [source] Survey Data and the Interest Rate Sensitivity of US Bank Stock ReturnsECONOMIC NOTES, Issue 2 2000H. A. Benink In this paper, we provide empirical evidence on the interest rate sensitivity of the stock returns of the twenty largest US bank holding companies. The main contribution of the paper is the use of survey data to model the unexpected interest rate variable, which is an alternative approach to the existing literature. We find evidence of significant negative interest rate sensitivity during the early 1980s, and evidence of declining significance in the late 1980s and early 1990s. This result is also obtained when using the forecast errors of ARIMA processes to model the unexpected movement in the interest rate. [source] The Adequacy of Household Survey Data for Evaluating the Nongroup Health Insurance MarketHEALTH SERVICES RESEARCH, Issue 4 2007Joel C. Cantor Objective. To evaluate the accuracy of household survey estimates of the size and composition of the nonelderly population covered by nongroup health insurance. Data Sources/Study Setting. Health insurance enrollment statistics reported to New Jersey insurance regulators. Household data from the following sources: the 2002 Current Population Survey (CPS)-March Demographic Supplement, the 1997 and 1999 National Surveys of America's Families (NSAF), the 2001 New Jersey Family Health Survey (NJFHS), a 2002 survey of known nongroup health insurance enrollees, a small 2004 survey testing alternative health insurance question wording. Study Design. To assess the extent of bias in estimates of the size of the nongroup health insurance market in New Jersey, enrollment trends are compared between official enrollment statistics reported by insurance carriers to state insurance regulators with estimates from three general population household surveys. Next, to evaluate possible bias in the demographic and socioeconomic composition of the New Jersey nongroup market, distributions of characteristics of the enrolled population are contrasted among general household surveys and a survey of known nongroup subscribers. Finally, based on inferences drawn from these comparisons, alternative health insurance question wording was developed and tested in a local survey to test the potential for misreporting enrollment in nongroup coverage in a low-income population. Data Collection/Extraction Methods. Data for nonelderly New Jersey residents from the 2002 CPS (n=5,028) and the 1997 and 1999 NSAF (n=6,467 and 7,272, respectively) were obtained from public sources. The 2001 NJFHS (n=5,580 nonelderly) was conducted for a sample drawn by random digit dialing and employed computer-assisted telephone interviews and trained, professional interviewers. Sampling weights are used to adjust for under-coverage of households without telephones and other factors. In addition, a modified version of the NJFHS was administered to a 2002 sample of known nongroup subscribers (n=1,398) using the same field methods. These lists were provided by four of the five largest New Jersey nongroup insurance carriers, which represented 95 percent of all nongroup enrollees in the state. Finally, a modified version of the NJFHS questionnaire was fielded using similar methods as part of a local health survey in New Brunswick, New Jersey, in 2004 (n=1,460 nonelderly). Principal Findings. General household sample surveys, including the widely used CPS, yield substantially higher estimates of nongroup enrollment compared with administrative totals and yield estimates of the characteristics of the nongroup population that vary greatly from a survey of known nongroup subscribers. A small survey testing a question about source of payment for direct-purchased coverage suggests than many public coverage enrollees report nongroup coverage. Conclusions. Nongroup health insurance has been subject to more than a decade of reform and is of continuing policy interest. Comparisons of unique data from a survey of known nongroup subscribers and administrative sources to household surveys strongly suggest that the latter overstates the number and misrepresent the composition of the nongroup population. Research on the nongroup market using available sources should be interpreted cautiously and survey methods should be reexamined. [source] Modelling Overdispersion for Complex Survey DataINTERNATIONAL STATISTICAL REVIEW, Issue 3 2001E.A. Molina Summary The population characteristics observed by selecting a complex sample from a finite identified population are the result of at least two processes: the process which generates the values attached to the units in the finite population, and the process of selecting the sample of units from the population. In this paper we propose that the resulting observations by viewed as the joint realization of both processes. We overcome the inherent difflculty in modelling the joint processes of generation and selection by exploring second moment and other simplifying assumptions. We obtain general expressions for the mean and covariance function of the joint processes and show that several overdispersion models discussed in the literature for the analysis of complex surveys are a direct consequence of our formulation, undere particular sampling schemes and population structures. Résumé Les caracté d'une population sont observées grâce à un échantillon complexe sélectionnéâ partir d'une poplation finie. Ces caractéristiques sont le résultat de l'échantillon des unités de ette population. Dans cet article, nous considérons que l'observation globale peut être vue comme une réalisation simultanée de ces deux processus. Nous tentons de surmonter la difficulté intrinsèque liée à la modélisation du double processus de génération et de sélection par une étude du moment d'ordre deux et en considérant d'autres hypothèses simplificatrices. Nous obtenons une expression générale pour la moyenne et la covariance liée au sondage complexes, sont une conséquence directe de notre formulation, losque l'on considère un plan de sondage particulier et une population ayant une structure spécifique. [source] Zimbabwe's Drought Relief Programme in the 1990s: A Re-Assessment Using Nationwide Household Survey DataJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2006Lauchlan T. Munro Zimbabwe's Drought Relief Programme was hailed in the 1980s and 1990s as an effective response to a food crisis in a poor country. International observers in particular credited the Programme with preventing famine and protecting livelihoods. Even before the current political turmoil and the ensuing politicisation of Drought Relief that have afflicted Zimbabwe since 2000, Zimbabwean authors were more sceptical about the effectiveness of Drought Relief. Both sides in the debate, however, failed to substantiate their arguments with national household survey data on who got what kind of assistance from Drought Relief, but rather relied on administrative data, qualitative interviews or sub-national surveys. Drawing its inspiration from WHO's minimum evaluation procedure, this article uses data from four nationwide household surveys in 1992,1993 and 1995,1996 and various definitions of poverty to ask whether Drought Relief provided poor people with relevant, timely and adequate assistance in the 1990s. The analysis suggests that Drought Relief was effective in supporting drought-affected smallholders during the 1990s. Drought Relief generally had a slight pro-poor bias. Unfortunately, Drought Relief since 2000 has a very different character. [source] The Quantification of Qualitative Survey Data: A Critical AssessmentJOURNAL OF ECONOMIC SURVEYS, Issue 5 2003Michela Nardo Abstract., Data obtained from business and consumer surveys are often used in forecasting models and in testing different expectation formation schemes. Their use, however, requires a previous step of transformation of the qualitative data into quantitative figures. This paper contains a critical review of the different quantification methods, highlighting the limits of their use in macroeconomic modelling. [source] Venture Capital Availability and Labor Market Performance in Industrial Countries: Evidence Based on Survey DataKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 1 2010Horst Feldmann SUMMARY This paper finds that more readily available venture capital is likely to have lowered unemployment rates and raised employment rates in industrial countries over the period 1982 to 2003. More readily available venture capital is also likely to have lowered the share of long-term unemployed in the total number of unemployed. The magnitude of the effects appears to have been substantial. To measure access to venture capital, we use answers from surveys of senior business executives. We also employ a large number of control variables. Our regression results are robust to variations in specification and sample size. [source] The Three Exit, Three Voice and Loyalty Framework: A Test with Survey Data on Local ServicesPOLITICAL STUDIES, Issue 2 2008Keith Dowding The article presents a modified Hirschman framework with three types of exit: moving location; moving from the public to a private sector provider; and moving between public sector providers; and three types of voice: private voice (complaining about private goods); voting; and collective action. Seven hypotheses are generated from this framework. The article then presents evidence from the first round of an online survey examining citizen satisfaction with public services and the relationship between exit and voice opportunities. We find dissatisfied people are more likely to complain privately, vote and engage in other forms of collective participation; but only a weak relationship exists between dissatisfaction and geographical exit. We find some evidence that the exit,voice trade-off might exist as more alert consumers are more likely to move from the public to the private sector and those ,locked in' are more likely to complain than those who have outside options. Overall the results tend to corroborate the hypotheses drawn from the modified Hirschman framework. [source] Role of Education in Cigarette Smoking: An Analysis of Malaysian Household Survey Data,ASIAN ECONOMIC JOURNAL, Issue 1 2009Andrew K.G. Tan D12; I21 Heckman's sample selection model is used to examine the role of education on household purchase decisions and expenditures of tobacco products in Malaysia. Results of the marginal effects of education, segmented by ethnic and gender groups, suggest that education decreases the probability, conditional levels and unconditional levels of tobacco expenditures amongst Malaysian households. Specifically, an additional year of education of the household head, irrespective of ethnic or gender considerations, decreases smoking probability by 1.5 percent. However, the negative effect of education seems to be higher for Chinese (US$1.07) than Malay (US$0.26) households in terms of conditional expenditures. Furthermore, education significantly decreases conditional tobacco expenditures within male-headed households. [source] GUARDIANSHIP IN CONTEXT: IMPLICATIONS FOR BURGLARY VICTIMIZATION RISK AND PREVENTION,CRIMINOLOGY, Issue 4 2007PAMELA WILCOX Survey data from 4,227 Seattle residents nested within 100 "neighborhoods" (census tracts) were analyzed to discern interrelationships between various dimensions of individual-level and neighborhood-level guardianship. We focused on four dimensions of guardianship,physical (target hardening), personal (home occupancy), social (informal control), and natural (surveillance through environmental design),at both individual and neighborhood levels. A multilevel opportunity, theoretical framework guided hypotheses, which suggests that each of the four dimensions of individual guardianship would be related more negatively to burglary as each of the four dimensions of aggregate guardianship increased. Multilevel logistic regression analysis revealed support for many of such hypothesized moderating effects of aggregate guardianship. More specifically, 6 of the 16 possible interaction effects were statistically significant at the .05 level and an additional 3 interaction effects were significant at the .10 level. In particular, individuallevel target hardening, place management, and natural surveillancewere related more negatively to burglary as neighborhood-level target hardening increased, as neighborhood-level informal social control increased, and as neighborhood-level natural surveillance increased. [source] Customer Behavior in an Online Ordering Application: A Decision Scoring Model,DECISION SCIENCES, Issue 4 2005Kenneth K. Boyer ABSTRACT This research presents the development of behavioral scoring models to predict future customer purchases in an online ordering application. Internet retailing lowers many barriers for customers switching between retailers for repeat purchases; thus, retaining existing customers is a key challenge for achieving profitability. Survey data were collected from 1,089 online customers of two companies. The subjective survey data were then used to predict purchases over the ensuing 12 months based on data from the company databases. The analysis illustrates the general applicability of predictive models of future customer purchases while also demonstrating the need to develop specific models tailored for an individual company's operating and marketing environment. The models provide insight on how companies can target marketing dollars more effectively and allocate investment across multiple operational areas for maximum return. The research answers a call for rigorous research in the area of predictive marketing, an area in which many companies are excelling but where there is a scarcity of detailed knowledge regarding application of such models. [source] Patients Spend More Time With the Physician for Excision of a Malignant Skin Lesion Than for Excision of a Benign Skin LesionDERMATOLOGIC SURGERY, Issue 3 2004Steven R. Feldman MD Background. Currently, there is a difference in reimbursement between excision of malignant and benign lesions. There is concern that there is not sufficient rationale for differential reimbursement for these two procedures. Objective. To assess whether there is a difference in physician work involved with excision of benign versus malignant skin tumors. Method. We searched National Ambulatory Medical Care Survey data for visits at which excision of benign and malignant skin lesions was performed. We compared the time spent with the physician at these two types of visits. To exclude confounding issues unrelated to the excision that would affect the time of visit, we excluded visits at which multiple diagnoses were addressed. Results. The mean time spent with the physician at visits for excision of benign lesions was 22.9±1.0 minutes. The mean time spent with the physician at visits for excision of malignant lesions was 30.0±1.7, 30% longer (p < 0.001). The longer time for excision of malignant lesions remained significant after controlling for age, gender, and race. Conclusion. Excision of malignant lesions involves more physician work than does excision of benign lesions. Elimination of differential compensation for benign versus malignant skin lesion procedures would not enhance the accuracy of reimbursement. In the absence of any compelling rationale to change the existing differential reimbursement, the proposals to do so are not warranted. [source] Frequency of Seborrheic Keratosis Biopsies in the United States: A Benchmark of Skin Lesion Care Quality and Cost EffectivenessDERMATOLOGIC SURGERY, Issue 8 2003Maria I. Duque MD Background. Most seborrheic keratoses may be readily clinically differentiated from skin cancer, but occasional lesions resemble atypical melanocytic neoplasms. Objective. To evaluate the frequency, cost, and intensity of procedures performed that result in the removal and histopathologic evaluation of seborrheic keratoses. Methods. Episodes of surgical removal of lesions that were identified as seborrheic keratoses by histologic identification were determined using Medicare Current Beneficiary Survey data from 1998 to 1999. These episodes were defined by a histopathology procedure code that is associated with a diagnosis code for seborrheic keratosis. We then identified what procedure(s) generated the histopathology specimen. Biopsy and shave procedures were considered "low intensity," whereas excision and repair procedures were considered "high intensity." Results. Dermatologists managed 85% of all episodes of seborrheic keratoses. Dermatologists managed 89% of seborrheic keratosis episodes using low-intensity procedures compared with 51% by other specialties. For nondermatologists, 46% of the treatment cost ($9 million) to Medicare was generated from high-intensity management compared with 15% by dermatologists ($6 million). Conclusion. There is a significant difference in the management of suspicious pigmented lesions between dermatologists and other specialists. This affects both the cost and quality of care. [source] Beauty Versus Medicine: The Nonphysician Practice of Dermatologic SurgeryDERMATOLOGIC SURGERY, Issue 4 2003Harold J. Brody MD Background This investigation was initiated because of a growing concern by the American Society for Dermatologic Surgery about the proliferation of nonphysicians practicing medicine and its impact on public health, safety, and welfare. Objective Prompted by an alarming rise in anecdotal reports among dermatologic surgeons, the study sought to determine whether there was a significant increase in the number of patients seeking corrective treatment due to complications from laser and light-based hair removal, subsurface laser/light rejuvenation techniques, chemical peels, microdermabrasion, injectables, and other cosmetic medical/surgical procedures performed by nonphysicians without adequate training or supervision. Methods A survey of 2,400 American Society for Dermatologic Surgery members in July 2001 and in-depth phone interviews with eight patients who experienced complications from nonphysicians performing cosmetic dermatologic surgery procedures were conducted. Results Survey data and qualitative research results attributed patient complications primarily to "nonphysician operators" such as cosmetic technicians, estheticians, and employees of medical/dental professionals who performed various invasive medical procedures outside of their scope of training or with inadequate or no physician supervision. Conclusion The results underscore the need for improved awareness, legislation, and enforcement regarding the nonphysician practice of medicine, along with further study of this issue. [source] Were the changes to Sweden's maintenance treatment policy 2000,06 related to changes in opiate-related mortality and morbidity?ADDICTION, Issue 9 2010Anders Romelsjö ABSTRACT Aims To analyse whether changes in maintenance treatment of opiate-dependent subjects in Sweden were related to changes in opiate-related mortality and inpatient care from 1998 to 2006. Design We collected data from surveys of methadone maintenance treatment units, of buprenorphine and methadone sales, and of mortality and inpatient care in Sweden. Setting Sweden. Participants Patients in maintenance treatment. Measurements Survey data of treatment policy to all units in 2003 and 2005. Trend tests and correlation analyses of data on sales, mortality, inpatient care and forensic investigations. Findings The surveys showed a marked change to a less restrictive policy, with increased use of ,take-away doses' and a reduction of discharges due to side misuse. The one-year retention rate stayed high. Sales of buprenorphine and methadone and the number of patients in treatment increased more than threefold from 2000 to 2006, with the greatest increase for buprenoprphine, introduced in year 2000. There was a significant 20,30% reduction in opiate-related mortality and inpatient care between 2000,2002 and 2004,2006 but not of other drug-related mortality and inpatient care. This decline was larger in Stockholm County, which had a less restricted treatment policy. However, a significant increase in buprenorphine- and methadone-related mortality occurred. For the study period 1998,2006, statistically significant declines occurred only in Stockholm County. Conclusions The liberalization of Sweden's drug policy correlated with an increase in maintenance treatment, a decrease in opiate-related mortality and inpatient care and an increase in deaths with methadone and buprenorphine in the tissues. [source] Consumption Over the Life CycleECONOMETRICA, Issue 1 2002Pierre-Olivier Gourinchas This paper estimates a structural model of optimal life-cycle consumption expenditures in the presence of realistic labor income uncertainty. We employ synthetic cohort techniques and Consumer Expenditure Survey data to construct average age-profiles of consumption and income over the working lives of typical households across different education and occupation groups. The model fits the profiles quite well. In addition to providing reasonable estimates of the discount rate and risk aversion, we find that consumer behavior changes strikingly over the life cycle. Young consumers behave as buffer-stock agents. Around age 40, the typical household starts accumulating liquid assets for retirement and its behavior mimics more closely that of a certainty equivalent consumer. Our methodology provides a natural decomposition of saving and wealth into its precautionary and life-cycle components. [source] INDUSTRIAL DYNAMICS AND THE NEOCLASSICAL GROWTH MODELECONOMIC INQUIRY, Issue 4 2009WILLIAM F. BLANKENAU This paper studies industry-level dynamics and demonstrates the ability of a modified neoclassical growth model to capture a range of empirical facts. The paper begins by using U.S. data to document skilled and unskilled labor trends within industry sector classifications as well as industry sector output trends. Using Current Population Survey data from 1968 to 2004, it is shown that the ratio of skilled workers to unskilled workers employed has risen in all industries. The absolute increase in this ratio was larger in the more skilled industries, while the growth rate was larger in the less skilled industries. Furthermore, using national income account data, it is shown that relatively high-skilled industries have accounted for an increasing share of output over time. A version of the neoclassical growth model is then constructed to match these observations. One important feature of this model is a structure that introduces new goods into the economy at each moment of time. The model is able to capture a rich set of labor market movements between sectors and between skill levels as well as changes in the relative output shares across industries, yet preserves many nice features of the neoclassical growth model.(JEL E13, J20, 030) [source] Did the National Minimum Wage Affect UK Prices?,FISCAL STUDIES, Issue 1 2010Jonathan Wadsworth J0; J3; D4 Abstract One potential channel through which the effects of the minimum wage could be directed is that firms that employ minimum-wage workers could have passed on any higher labour costs resulting from the minimum wage in the form of higher prices. This study looks at the effects of the minimum wage on the prices of UK goods and services by comparing prices of goods and services produced by industries in which UK minimum-wage workers make up a substantial share of total costs with prices of goods and services that make less use of minimum-wage labour. Using sectoral-level price data matched to Labour Force Survey data on the share of minimum-wage workers in each sector, it is hard to find much evidence of significant price changes in the months that correspond immediately to the uprating of the national minimum wage. However, over the longer term, prices in several minimum-wage sectors , notably, take-away food, canteen meals, hotel services and domestic services , do appear to have risen significantly faster than prices in non-minimum-wage sectors. These effects were particularly significant in the four years immediately after the introduction of the minimum wage. [source] The Take-Up of Multiple Means-Tested Benefits by British Pensioners: Evidence from the Family Resources SurveyFISCAL STUDIES, Issue 3 2004RUTH HANCOCK Non-take-up of means-tested benefits among pensioners is of long-standing concern. It has assumed increased importance from October 2003 with the introduction of the new means-tested pension credit to which about half of pensioners are expected to be entitled. We use Family Resources Survey data from April 1997 to March 2000 to investigate patterns of pensioner take-up of income support (IS) (subsequently renamed the minimum income guarantee and now subsumed in pension credit), housing benefit (HB) and council tax benefit (CTB). Although 36 per cent of pensioners in our sample failed to claim their entitlements to at least one of these benefits, only 16 per cent failed to claim amounts worth more than 10 per cent of their disposable income. Generally, take-up is high where entitlement is high. But there are exceptions which may reflect the claims process and/or a greater degree of social stigma associated with IS than with HB or CTB. [source] Effects of drought on avian community structureGLOBAL CHANGE BIOLOGY, Issue 8 2010THOMAS P. ALBRIGHT Abstract Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioural traits, what time periods and indicators of drought are most relevant, or how response varies geographically at broad spatial scales. Our goals were thus to determine (1) how avian abundance and species richness are related to drought, (2) whether community variations are more related to vegetation vigour or precipitation deviations and at what time periods relationships were strongest, (3) how response varies among avian guilds, and (4) how response varies among ecoregions with different precipitation regimes. Using mixed effect models and 1989,2005 North American Breeding Bird Survey data over the central United States, we examined the response to 10 precipitation- and greenness-based metrics by abundance and species richness of the avian community overall, and of four behavioural guilds. Drought was associated with the most negative impacts on avifauna in the semiarid Great Plains, while positive responses were observed in montane areas. Our models predict that in the plains, Neotropical migrants respond the most negatively to extreme drought, decreasing by 13.2% and 6.0% in abundance and richness, while permanent resident abundance and richness increase by 11.5% and 3.6%, respectively in montane areas. In most cases, response of abundance was greater than richness and models based on precipitation metrics spanning 32-week time periods were more supported than those covering shorter time periods and those based on greenness. While drought is but one of myriad environmental variations birds encounter, our results indicate that drought is capable of imposing sizable shifts in abundance, richness, and composition on avian communities, an important implication of a more climatically variable future. [source] Avifauna response to hurricanes: regional changes in community similarityGLOBAL CHANGE BIOLOGY, Issue 3 2010CHADWICK D. RITTENHOUSE Abstract Global climate models predict increases in the frequency and intensity of extreme climatic events such as hurricanes, which may abruptly alter ecological processes in forests and thus affect avian diversity. Developing appropriate conservation measures necessitates identifying patterns of avifauna response to hurricanes. We sought to answer two questions: (1) does avian diversity, measured as community similarity, abundance, and species richness, change in areas affected by hurricane compared with unaffected areas, and (2) what factors are associated with the change(s) in avian diversity? We used North American Breeding Bird Survey data, hurricane track information, and a time series of Landsat images in a repeated measures framework to answer these questions. Our results show a decrease in community similarity in the first posthurricane breeding season for all species as a group, and for species that nest in the midstory and canopy. We also found significant effects of hurricanes on abundance for species that breed in urban and woodland habitats, but not on the richness of any guild. In total, hurricanes produced regional changes in community similarity largely without significant loss of richness or overall avian abundance. We identified several potential mechanisms for these changes in avian diversity, including hurricane-induced changes in forest habitat and the use of refugia by birds displaced from hurricane-damaged forests. The prospect of increasing frequency and intensity of hurricanes is not likely to invoke a conservation crisis for birds provided we maintain sufficient forest habitat so that avifauna can respond to hurricanes by shifting to areas of suitable habitat. [source] Assessing the effects of hydromorphological degradation on macroinvertebrate indicators in rivers: examples, constraints, and outlookINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 1 2009Nikolai Friberg Abstract An extensive amount of literature on linkages between the in-stream physical environment and river benthic macroinvertebrates reports a number of relationships across multiple spatial scales. We analyzed data on different spatial scales to elucidate the linkages between different measurements of hydromorphological degradation and commonly used macroinvertebrate indices. A regression analysis of 1049 sites from 3 countries revealed that the strongest relationship between a biotic metric,average score per taxon,and physiochemical variables (R2 = 0.61) was obtained with a multiple regression model that included concentration of total phosphorus and percent arable land in the catchment, as well as hydromorphological quality variables. Analyses of 3 data sets from streams primarily affected by hydromorphological degradation showed an overall weak relationship (max R2 = 0.25) with the River Habitat Survey data of 28 Swedish streams, whereas moderate (R2 , 0.43) relationships with more detailed measurements of morphology were found in 2 Danish studies (39 and 6 streams, respectively). Although evidence exists in the literature on the importance of physical features for in-stream biota in general and macroinvertebrates specifically, we found only relatively weak relationships between various measures of hydromorphological stress and commonly used macroinvertebrate assessment tools. We attribute this to a combination of factors, including 1) the mixed nature of pressures acting on the majority of river reaches, 2) scaling issues (spatial and temporal) when relating habitat surveys to macroinvertebrate assessments, and 3) the scope of commonly used macroinvertebrate assessment systems (mainly focusing on water chemistry perturbation, such as eutrophication and acidification). The need is urgent to develop refined and updated biological assessment systems targeting hydromorphological stress for the use of the European Water Framework Directive (WFD) and national water-related policies. [source] Mumbai's Mysterious Middle ClassINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 4 2006JAN NIJMAN Mumbai forms the décor to an interesting set of relationships among economic liberalization, globalization, class restructuring and an unprecedented housing construction boom. The much talked about new Indian middle class is primarily an urban phenomenon and seems nowhere more salient than in India's commercial capital and largest city. This article seeks to undo some of the mysteries that surround the new middle class: how it can be empirically defined, whether and how it is growing, how class restructuring in Mumbai conforms (or not) to Western arguments about social polarization, and how any such class restructuring can best be explained. The empirical analysis employs existing data from various sources on income and consumption in Mumbai (and India at large) and reports on selected findings from a recent survey by the author on housing, class and upward mobility among households in newly constructed homes in Greater Mumbai. Data on the distribution of household incomes show that the upper-middle income classes have grown relative to the total, that the lower-middle income classes have shrunk, and that the ranks of the poor have expanded slightly. Survey data among new home buyers in Mumbai suggest little upward mobility. Discourse about the ,new middle class' tends to focus on consumption rather than income and additional findings indicate that much of the growth in consumption is credit-based. [source] Does Selective Migration Matter?INTERNATIONAL MIGRATION REVIEW, Issue 4 2005Explaining Ethnic Disparities in Educational Attainment among Immigrants'Children Understanding why some national-origin groups excel in school while others do not is an enduring sociological puzzle. This paper examines whether the degree of immigrants'educational selectivity - that is, how immigrants differ educationally from non-migrants in the home country - influences educational outcomes among groups of immigrants'children. This study uses published international data and U. S. Census and Current Population Survey data on 32 immigrant groups to show that as immigrants'educational selectivity increases, the college attainment of the second generation also increases. Moreover, the more positive selection of Asian immigrants helps explain their second generations'higher college attendance rates as compared to Europeans, Afro-Caribbeans, and Latinos. Thus, the findings suggest that inequalities in relative pre-migration educational attainments among immigrants are often reproduced among the next generation in the United States. [source] Relationships of Sexual Abuse, Connectedness, and Loneliness to Perceived Well-Being in Homeless YouthJOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 2 2002Lynn RewArticle first published online: 23 FEB 200 ISSUES AND PURPOSE. To describe respondents' perceptions of connectedness, loneliness, and well-being; and to explore relationships among these variables. DESIGN AND METHOD. Survey data from 96 participants, focus group interviews with 32 participants, and 10 individual interviews were analyzed. RESULTS. Sixty percent of the sample reported sexual abuse, which was significantly related to loneliness and inversely related to connectedness and perceived well-being. Subjects felt lonely and disconnected. They perceived their well-being in terms of current health status. PRACTICE IMPLICATIONS. High rates of sexual abuse, lack of connectedness, and loneliness may help to explain poor perceived well-being in homeless youth. [source] Asthma Pharmacotherapy Prescribing in the Ambulatory Population of the United States: Evidence of Nonadherence to National Guidelines and Implications for Elderly PeopleJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 7 2008Prakash Navaratnam MPH OBJECTIVES: To examine the level of physician adherence to the Expert Panel Report 2 (EPR-2) pharmacotherapy guidelines of the asthma population, specifically in the elderly ambulatory patient population of the United States. DESIGN: Retrospective cross-sectional study using a national survey. SETTING: National Ambulatory Medical Care Survey data of U.S. elderly patients from 1998 through 2004. PARTICIPANTS: The weighted population sample size was 82,020,318 patients. There were 1,540 observations in this study (preweighted sample size) and 96 strata, with 446 population sampling units (PSUs). There were 11,868,340 patients that were elderly, and they accounted for 14.5% of the overall population sampled. MEASUREMENTS: Specific patient demographic variables, physician demographic variables, and information about asthma medications prescribed were extracted from the data set and analyzed. Descriptive statistics for the patient demographic, physician demographic, and asthma pharmacotherapy variables were generated. A series of logistic regression models were created, with the choice of asthma pharmacotherapy agent used as the dependent variable and patient and physician demographic variables as the independent variables. RESULTS: A major finding was that physicians were not adherent to the National Asthma Education and Prevention Program EPR-2 asthma pharmacotherapy guidelines. Another finding was that, although elderly patients (aged ,65) were exposed to more-stable patterns of care, they were less likely to be prescribed controller medications, long-acting bronchodilators (LABAs), combinations of inhaled corticosteroids and LABAs, and short-acting beta agonists than patients aged 35 to 64. CONCLUSION: A more-concerted effort needs to be undertaken to improve physician adherence to the EPR-2 guidelines, especially in prescribing asthma pharmacotherapy to elderly patients. [source] The rate of learning-by-doing: estimates from a search-matching modelJOURNAL OF APPLIED ECONOMETRICS, Issue 6 2010Julien Prat We construct and estimate by maximum likelihood a job search model where wages are set by Nash bargaining and idiosyncratic productivity follows a geometric Brownian motion. The proposed framework enables us to endogenize job destruction and to estimate the rate of learning-by-doing. Although the range of the observations is not independent of the parameters, we establish that the estimators satisfy asymptotic normality. The structural model is estimated using Current Population Survey data on accepted wages and employment durations. We show that it accurately captures the joint distribution of wages and job spells. We find that the rate of learning-by-doing has an important positive effect on aggregate output and a small impact on employment. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||||||||